During the Second World War, the city of Wuppertal suffered numerous Allied air raids, primarily nighttime attacks from the Royal Air Force's Bomber Command during its Battle of the Ruhr bomber offensive.
Overall, more than 6,500 people lost their lives during World War II in Wuppertal from such raids; 38 percent of the built-up urban area was destroyed.
New aircraft designs which made extensive use of wooden airframe components, such as the Focke-Wulf Ta 154 Moskito and the Heinkel He 162 Spatz, had their development seriously delayed or even temporarily curtailed as a result of the deficient replacement adhesive corroding the wooden airframes of the aircraft, resulting in crashes of the prototype airframes of both defensive fighter designs.
The progress on the Ta 154's development — which occurred nearly a year before the He 162's first prototypes were built — and exactly when the corrosive replacement adhesive was first used for building its production airframe series, throw doubt on the early February 1943 date.)
The RAF dropped timed explosives that caused the foundations of buildings to literally melt away.